Plunger actuated hold-down clamp



Sept. 20, 1949. R. E. GoRDlNlER A A2,482,708

n v I PLUNGER ACTUATED HOLD-DOWN CLAMP l Filed J-une 29, 1944 F11-Eni..

INVENToR. 1 f Pfl/.PH E. Gana/MER Patented Sept. 2Q, 1949 PLUNGER ACTUATED HOLD-DOWN CLAMP Ralph E. Gordinier, Detroit, Mich., assigner to Special Engineering Service, Incorporated, Detroit, Mich., a corporationvof' Michigan Application J une 29, 1944, Serial No. 542,759

2 Claims.

This invention relates to a pro-duction clamp.

As a work holder for production of small pieces, it is sometimes desirable to provide a smal] clamp for locking identical pieces in position 4beforera workman for -a small operation. It is also desirable that this clamp be readily opened and closed. A great degree of movement is not necessary since the clamp would be set up for any particular .piece of work.

The present invention contemplates a small but sturdy clamp which is intended particularly for use in production work. Other objects and features of the invention relating to details of design lwill be evident from the following description and claims.

In the drawings:

Fig. 1 is a vertical section of the assembly in operative position.

Fig. 2 is a plan view of the clamp.

Fig. 3 is an elevation of the clamping end.

Fig. 4 is a section on line 4 4 of Fig. 1.

In the drawings, a base I having side flanges II is provided with a cylindrical opening I2. Slidable in :the 'opening I2 is a cylindrically shaped plunger I5 which is provided at one end with a slot I6 and lat the other end with a bore I'I ensmalled at its outer end to form a Wall IB and an opening I9.

Within the slot I6 of plunger I5 is mounted a T-shaped clamping dog having an extending nose 2| for clamping purposes and a projection 22 for operating purposes. This dog is mounted on a pin 23 which passes through fthe dog and into holes on either side of plunger I 5.

Slidable within :the bore Il of plunger I5 is an operating stud 33. One end 3| of the stud is threaded and passes through the opening I9 of plunger I5 into a threaded handle 32. The other end of the stud is enlarged to a shoulder 33 which retains a spring 33a in the bore of plunger I5 and against shoulder I8. This enlarged end 34 of stud 3i) is provided with a recess cylindrical in nature but positioned at an langle to the axis of the stud so that a surface 35 is formed as shown in Fig. 1. The projection 22 from dog 20 is shaped to nt into the recess in the stud and has a ball 35 mounted in its lower surface to cooperate with surface 35 of the stud.

A slot 4S is formed in the side of plunger I 5 to cooperate with a locking screw 4I. With the screw in place as shown in Fig. 2 the plunger I5 can be shifted back and forth in the bore I2 `so that the nose 2l may take various positions relative to the base IB. At any one of these positions handle 32 may be turned to the right to pull stud Y ball 36 to ride up on surface 35 and tilt the nose c clamping leverage.

2i downward to the point where it contacts 'and clamps the work. To release the work, the handle 32 may be rotated in the opposite direction. Spring 5:33a will then `press against the stud end 3imoving it to the right as shown in Fig. 1. A projection 5@ on stud end 34 moves against the lower portion of dog Zi and causes upward movement of the nose 2|. Thus there is positive locking and positive rele-ase. The locking force applied by nose 2| -also'locks the pl-unger I5 in any position it is placed for a particular job.

Referring to Fig. 1, is will be seen that if Ia downward force is exerted by nose 2 I a downward reaction will be exerted by member 22 yon stud end 34. To prevent Vbinding of the stud a large bearing surface has been provided as shown in Fig, 4. The cylindrical section of member 34 bears through in its recess I6 in 4plunger I5. With this design there is no binding when great forces are applied through the tremendous leverage of the screw 3 I.

The angle of surface 35 to the horizontal is also important. It is shown as 30. This must be correlated with the pitch of threads 3l to the eX- tent that a relatively short movement of stud end 34 gives the desired clamping movement and An angle of from 25 to 35 has been found most satisfactory.

I claim:

1. A. production clamp comprising a base having an elongated horizontal opening therethrough, a plunger in the form of a self-contained cartridge unit slidably mounted in said opening and having a recess formed in one end thereof, a lever mounted in said recess for pivotal movement in a vertical plane and having a pair of downwardly projecting* hook portions on opposite sides of its pivotal support, one of said hook portions being arranged to extend out oi the opening in said base and the other hook portion extending into said recess, a slide member in said recess having a threaded shank projecting out through the end of said plunger remote from said lever, a hand wheel threadedly engaged with said shank and having a bearing surface arranged to bear against the adjacent end face of said plunger, said slide member having an inclined surface at the inner end thereof co-acting with and disposed beneath the inwardly extending hook portion of said lever so as to pivot said hook portion upwardly when the slide member is actuated by said hand wheel in a direction away from said lever and thereby pivot the outwardly extending hook portion downwardly with a clamping pressure against an object disposed beneath it.

2. A production clamp comprising a base having an elongated horizontal opening therethrough, a plunger in the form of a self-contained cartridge unit slidably mounted in said opening and having a recess formed in one end thereof, a lever pivoted in said recess on a horizontal axis transversely of the aXis of said plunger, said lever having a pair of downwardly hooked portions thereon on opposite sides of its pivotal aXis, one of said hook portions extending out of the opening in said base and the other hook portion extending into said recess, said inwardly eX- tending hook portion having a downwardly facing surface thereon inclined downwardly and away from the pivotal aXis of said lever, an actuating member slidably mounted in said recess and having a threadedshank projecting out through the end of said plunger remote from said lever, a hand wheel threaded on said projecting shank portion and having a surface disposed to bear against the adjacent end face of said plunger, said actuating member having a surface at the inner end thereof inclined upwardly in the direction of said lever, said upwardly inclined surface being arranged beneath the downwardly inclined surface of said inwardly extending hook portion, and a ball member mounted in the inclined face of said hook portion, said ball member projecting into the lpath of movement of the inclined face of said actuating member whereby when said hand Wheel is actuated to slide said actuating member within said recess in a direction away from said lever, said ball member rides up the inclined face of said actuating member to pivot the inwardly extending hook portion of said lever upwardly and the outwardly extending portion downwardly with a clamping pressure against an object arranged beneath said outwardly extending hook portion, said plunger being locked in position in the opening in said base by the clamping pressure exerted by said outwardly extending portion.

RALPH E. GORDNIER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 310,839 Mickel Jan. 13, 1885 492,435 Rittenhouse Feb. 28, 1893 492,931 Baird Mar. 7, 1893 1,022,761 Stvanek Apr. 9, 1912 1,220,423 Huisinger et al Mar. 27, 1917 1,424,034 Rigert July 25, 1922 1,383,429 Russell July 5, 1929 1,822,501 Onsrud Sept. 8, 1931 1,954,444 Early Apr. l0, 1934 FOREGN PATENTS Number Country Date 56,426 Sweden Apr. 1, 1924 

